Environmental change and increasing movements of people, animals and plants, have led to parasite introductions into new areas, breaking down ecological isolation barriers. This can result in novel host-parasite and parasite-parasite interactions, including hybridization and introgression of genes into the gene pool of other species. These phenomena can accelerate invasion through the creation of extreme ( transgressive ) phenotypes, but can also lead to the emergence of new diseases, including zoonoses. Here we discuss the recent emergence of urinary schistosomiasis in Corsica, which is caused by a hybrid schistosome species. It is a hybrid cross between a human and an animal schistosome species and it can infect both humans and livestock. With molecular tools we aim to reconstruct the source of introduction into Corsica and characterize the local intermediate snail host. Microsatellite analyses point to a close affiliation with the Senegalese hybrid strains and possible scenarios will be discussed. Given the fact that the intermediate snail host Bulinus truncatus is endemic in southern Europe, close monitoring of putative transmission sites is highly recommended.